Duplex pumping engine



(No Model.)

I V 3 SheetsSheet 1. P. F. ODDIE 8; G. HESSE. DUPLEX PUMPING ENGINE.

No. 593,490. Patented Nov. 9,1897.

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(No Model.) 3 Sheets-Sheet 2.

P. P. ODDIB 8: G. HESSE. DUPLEX PUMPING ENGINE.

No. 593,490. Patented Nov. 9,1897.

P17165565 Inzlznlbm aiturngy (No Model.) 3 Sheets-Sheet 3.

P. F. ODDIE 8v G.=HESSE. DUPLEX PUMPING ENGINE.

No. 593,490. Patented Nov. 9,1897.

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UNITED STATE PATENT OFFICE.

PHILIP FRANCIS ODDIE AND GUSTAVHESSE, OF LONDON, ENGLAND.

DUPLEX PUMPING-ENGINE.

SPECIFICATION forming part of Letters Patent No. 593,490, dated November 9, 1897.

Application filed April 19, 1897. Serial No. 632,824. (No model.)

T0 aZZ whom, it may concern:

Be it known that we, PHILIP FRANCIS OD- DIE, a subject of the Queen of Great Britain, and GUSTAV IIEssE, asubject of the German Emperor, engineers, residing at125 and 130 Larkhall Lane, Olapham, London, in the county of Surrey, England, have invented certain new and useful Improvements in Duplex Pumping-Engines, of which the following is a specification.

This invention has reference to improvements in duplex pumping-engines to simplify their operation, add to their efficiency, and effect economy of steam.

In a duplex pumping-engine which we have previously constructed each piston is formed with an inclined groove or guide adapted to effect the operation of the valve controlling the supply of steam to the companion or duplicate cylinder and an arrangement of expansion-valves working on the back of, or through, the main valves operated by the same groove or guide formed on the pisi ons and controlling admission of steam to its own cylinder.

In the present invention, instead of forming the inclined groove on the pistons, it is formed on or in separate rods or bars, which are located in the valve-chest. One end of each of these bars is continued through suitable stufiing-boxes and'is in connection with projecting arms rigidly fixed on each pistonrod. Each bar is free to reciprocate within the valve-chest in a line parallel with the motion of the pistons, any lateral movement being prevented by suitable guides, preferably fixed on the valve-chest covers. The valves for the admission and emission of steam are formed with inclined parts corresponding with and engaging in the inclined portion on the bars. When the pistons reciprocate within their respective cylinders, each bar or rod reciprocates also, imparting to the main and expansion valves a reduced motion in a line at right angles to the line of motion of the pistons. The connection between the projecting arms on the piston-rods and the extending ends of the bars is made by means of adjustable collars or nuts or other suitable arrangement, so as to provide a certain amount of lost motion or slack between the travel of the pistons and that of the bar or rod.

In the drawings, Figure 1 is a longitudinal sectional view through one of the cylinders of a duplex pumping-engine. Fig. 2 is a sectional plan view taken on the line A B,- Fig. 1, with the valves and rods removed in order to show the valve-faces. Fig. 3 is a plan view of the main steam-valves and expansionvalves separately. Fig. 4 is a sectional view taken on the line E F, Fig. 3. Fig. 5 is a plan view of one of the main valves with the expansion-valve removed. Fig. 6 shows plan views of the bars or blocks and rods, one block having a right-hand slot or groove and the other a left-hand. Fig. 7 is-a cross-sectional view taken on the line 0 D, Fig. 2, showing the guides for the reciprocating blocks. Fig. 8 shows by side view, and Fig. 9 by plan view, on a larger scale than the previous figures, an alternative arrangement in which the lost motion is provided for within the valve-chest instead of outside, as shown in Fig. 1. Fig. 10 is a cross-sectional view through one of the reciprocating blocks. Fig. 11 is a cross-sectional view'through one of the main steam-valves and expansion-valves. Fig. 12 is a longitudinal sectional view showing both steam end and pump end,to a smaller scale, with the lost motion arrangement shown in Figs. 8 to 10 applied thereto. Figs. 13, 1d, 15, 16, 17, and 18 show details ready to be assembled in their positions in the valvechest.

a is the steam-piston, and a the piston-rod.-

b is the valve-chest or steam-chest with cover I).

c is an arm rigidly attached to the pistonrod a and conveying reciprocating motion to a rod d, connected to a bar or block 61.

d and d (see Figs. 1 and 6) are adjustable collars on the rod d, by regulating which the travel of the block can be varied.

e is a main steam-valve, and f an expansion-valve.

g g are steam-inlet passages communicating with the ends of their respective cylinders, and h h are exhaust-passages. (See Figs. 2 and 7.) 7

Referring to Figs. 3, 4, 5, ,11, 15, and 16, e e are the main steam-valves, f f are the expansion-valves, and 71 z" are inclined driving-pieces which engage with corresponding inclined slots 76 k in the sliding blocks cl d. (See Figs. 6, 14, and 17.) Suitable guides 19*,

Fig. 7, are formed in the valve-chest cover to prevent lateral movement of the bars cl 01.

As shown in Fig. 1, lost motion is obtained to the desired extent by allowing the fixed arm 0 on the piston-rod a to travel between the adjustable nuts 61 d on the sliding rod d. In some cases it may be preferable to have the lost motion take place in the valve-chest, as shown in Figs. 8, 9, 10, and 12. In this arrangement the outer end of the rod (1 is attached to the arm 0 by means of a screwthread (1 formed on the rod d, the inner end of the said rod being provided with a screwthread d and nut d, the pitch of this thread being double that of (1 A hand-wheel d may be provided at the outer end of the rod 61 for convenience of turning the same to regulate the travel and cut-off of the valves. The guide-piece 11 (see Figs. 11 and 18) has a stem 4?, which passes through the expansion and main valves and serves to fix them together.

Z is a pump-cylinder, and m the water-piston.

As shown, two steam-pumps are placed side by side, and the arrangement is such that each piston while actuating the main slidevalve for the other has also control over its own steam admission by means of a cut-oft valve working on the back of the main valve.

In order to obtain the requisite main-valve movement, it is obvious that one slot in the driving-blocks d has to lie inclined in a righthand direction and the other in a left. This supplies the place of the long and short levers in the ordinary duplex-valve motion. Referring to Fig. 12, let it be supposed that the piston is traveling in the direction of the arrow and steam entering through port g in the cylinder, Fig. 13, and corresponding port 9 in main valve 6, Fig. 15. The main valve e, Fig. 16, to which the double-pronged expansion-valve f is attached, is being driven in the direction of the arrow, Fig. 16, and the inner edge f of this double-pronged valve f, passing over the valve-port g Fig. 15, cuts off the steam. The port g, Fig. 13, is now open, and the steam is driving the fellow piston. This piston moves the main valve e, to which the single-pronged expansion-valve f is attached, in the direction of the arrow, Fig. 15, and the outer edge f of the valve f passes over the port 9 Fig. 16, and cuts off the steam. On the return strokes the motions are reversed. It will be seen that the-same direction of motion of the piston drives the valves in opposite directions. Hence the necessity of one expansion-valve being an inside cut-off valve and the other an outside cut-off valve, the valve f cutting off on its outside edges f f and the valve f cutting oif on its inside edges f f In addition to the economy secured by the absence of short strokes and the expansive working of the steam. this improved pump can be run smoothly and quietly without shock or jar of the water-column at considerably greater speeds than those hitherto attainable with the ordinary duplex pump. This advantage is due to the action of the cutofi valves, which cause the pistons to slow down toward and pause at the end of the stroke. Thisallows the pump-valves ample time to seat themselves quietly before the return stroke.

Having now particularly described and ascertained the nature of our said invention and in what manner the same is to be performed, we declare that what we claim is 1. In a duplex pumping-engine, the combination with the two cylinders each having its steam-passages in a line at right angles to the line of travel-of the pistons and each provided with a main valve, the steam-chest and an expansion-valve carried by each main valve, of sliding inclined-faced blocks each engaged with a correspondingly-inclined part of an expansion-valve and actuated from a pistonrod of the engine, so as to cause each expansion-valve to control the admission of steam to the main valve of the opposite cylinder, substantially as set forth.

2. In a duplex pumping-engine, the combination with the steam-chest and the two cylinders each having its steam-passages in a line at right angles to the line of travel of the pistons and each provided with a main valve, of expansion-valves carried by said main valves and each provided with an inclined guide part, sliding blocks having inclined slots engaged with the inclined guide parts of said expansion-valve, the slot of one block being inclined to the right and the other to the left, and means for actuating said sliding blocks from the piston-rods of the engine,

whereby each expansion-valve will control the ad mission of steam to the main valve of the opposite cylinder, substantially as set forth.

3. In a duplex pumping-engine, the combination with the two cylinders each having its steam-passages in a line at right angles to the line of travel of the pistons, a steam-chest, the main valves, and expansion-valves carried by the main valves and each provided with an inclined guide part, the guide part of one expansion-valve being inclined to the right and the other to the left, of sliding blocks having inclined slots engaged with the inclined guide parts of said expansion-valves, and means for imparting to said blocks in a reduced degree the motion of the engine piston-rods, substantially as set forth.

4. In a duplex pumping-engine, the combination with the cylinders each having its steam-passages in a line at right angles to the line of travel of the pistons, a steam-chest, and a combined main valve and expansionvalve for each cylinder, of sliding blocks each having an inclined face engaging a correspondingly-inclined part of an expansionvalve, and means for actuating said sliding blocks to an adj ustably-regulated extent from the piston-rods of the engine, to cause each steam to the main valve of the opposite cylinder, substantially as set forth.

blocks from the piston-rods of the engine, and adjusting mechanism to regulate the extent of throw for each block to cause each expansion-valve to control the admission of steam to the main valve of the opposite cylinder, substantially as set forth.

In testimony whereof We have hereunto set our hands in presence of two subscribing witnesses.

PHILIP FRANCIS ODDIE. GUSTAV HESSE. Witnesses:

ALFRED GEORGE BROOKES, JOHN GoonE How. 

